I have installed a new blower motor and AC compressor. All was working fine for 50 or so miles. Now the blower motor won't turn on and the AC compress clutch doesn't engage. I assume that the compressor clutch is a side effect of the blower motor. Does the blower motor have a fuse? It's an 87 MC SS. Is it a relay issue? Any pointers would be greatly appreciated.

Thanks,
Chad

I would check the fuse first, above your left knee behind the dash, good luck.

You may want to pull your climate control head unit out and inspect the brown 14ga wire which is protected by a 25 htr fuse at your fuseblock. For low, low-medium and medium fan speeds this wire supplies the power to your switch selector and it can overheat and short out @ the grey connector just behind and above the climate control unit. Check your selector switch for shorts too. To have a bad comp and blower, I'd suspect a disruption of voltage coming to the climate control unit.

Thanks for the suggestion. I had already checked the AC fuse and it is good. Does the blower motor have it's own fuse? Does it piggy back on something else? I need help identifying it.

Thanks,
Chad

Sounds like I will pull the climate control head unit out tonight. Thanks for the assistance.

Chad

Well for fun I replaced the 25 amp AC fuse. Started up my beast, turned on the ac and it kicked on very briefly. Looked at the new fuse and it was clearly blown. Replaced it and repeat. So what would cause the fuse to keep blowing.

Thanks,
Chad

Check for a pinched wire. there is one area that is problematic, in the HVAC harness just about over the valve cover behind the Alternator, there is a 4 way plug, these get overheated and start to melt, causing poor connections and resistance to electrical flow, check this area too, good luck.

AC compressor won't go on if the Freon pressure is too low.

but the blower motor will still run!

Don't overlook the wiring at the A/C compressors clutch.

A faulty compressor clutch is not out of the realm of possibilities too.